A225: The Investigation of the Regulation of the Process of Epithelial Mesenchymal Transition in Triple Negative and Basal Like Breast Cancer

Arwa Flemban1,Anthony Rhodes1,David Qualtrough1

1University of West of England, Bristol, Avon, UK

Presenting date: Monday 2 November
Presenting time: 12.20-13.10

Background

Breast cancer is the second leading cause of death in females and accounts for 15% of female deaths in the UK. Advances in medicine and understanding the molecular pathogenesis of breast cancer has resulted in improved survival rate of women with breast cancer. Nonetheless, Low survival rates remained in triple negative (TNBC) and basal-like breast cancer (BLBC) due to lack of expression molecular targets for therapy in those subtypes, highlighting the necessity for identifying new prognostic and targeted therapy markers in those subtypes, in which there is an increased rate of metastatic spread. 
The process of epithelial mesenchymal transition (EMT) is associated with metastasis of cancers such as melanoma and colon cancer. The study of EMT in breast cancer lacks the availability of suitable cell line in vitro models to investigate this process. 
This study aims to develop an in vitro model to investigate the EMT process. In addition, it aims to use this model for the investigation of the regulation of the process of epithelial mesenchymal transition (EMT) in triple negative breast cancer (TNBC), and basal-like breast cancer (BLBC).

Method

Tissue culture: BT-20, MDA-MB-231 (TNBC and Basal), MDA-MB-453 (TNBC), MCF7 (Luminal) were seeded in three seeding densities (High, Medium, and Low). Proteins were collected and concentrations were calculated to preform western blotting to investigate the difference of proteins expression including (E-cadherin, beta-catenin, vimentin, alpha-smooth muscle actin, and N-cadherin). Immunofluorescence: E-cadherin, CK7 (epithelial), CK5 (basal), beta-catenin (EMT), and Vimentin(mesenchymal).

Results

Initial morphological examinations showed that there is variation of the shape of the cells associated with variation in the seeding density. Then, protein analysis were conducted on cell lysates from these densities and investigation of the expression of epithelial, basal and EMT markers showed that they vary according to the seeding density with increase in epithelial markers in the medium seeding density of TNBC and BLBC cells. The investigation of the localisation of these markers showed that there is variation in the localisation of some marker according to the seeding density. 

Conclusion

It can be concluded that this model provides an opportunity to study the process of EMT in breast cancer cells. Additionally, this study showed evidence that the regulation of process of EMT is altered in TNBC and BLBC.